KVUE — The 24-year-old suspect accused of setting off a string of bombs in the Austin area is dead after detonating a device and killing himself, Austin police have confirmed. Austin police are warning the public that there may be other devices out there and to remain vigilant. (To see an example of a suspicious package, go here.)

Austin Police Chief Brian Manley said the suspect, identified as a 24-year-old white man, was identified by police in the past 24 hours as a person of interest. The man then became a suspect.

Authorities said they used surveillance video from the FedEx store on Brodie Lane in South Austin to lead them to the suspect, according to KVUE's Tony Plohetski. Authorities also got information from Google and from the suspect's computer history that confirmed the suspect was looking at information on where to go to ship devices, according to Plohetski's sources.

WFAA's Jason Whitely said law enforcement had identified the suspect at approximately 9 pm Tuesday, March 20, and were closing in on him based on packages he sent from FedEx. Whitely added that police wanted to surprise the man.

Authorities located the vehicle the suspect was known to be driving and found it at a hotel in Round Rock, Manley said.

Multiple officers from the Austin Police Department and federal agencies took positions around the hotel as they awaited the arrival of tactical teams, according to Manley.

The vehicle started to drive away, and authorities followed the suspect. Manley said the suspect's vehicle stopped in a ditch on the side of the road. As a SWAT team approached the vehicle, the suspect detonated a device, Manley said. The explosion knocked an officer back, causing the officer to suffer minor injuries. Another officer who Manley said has been with the department for 11 years then fired at the vehicle. That officer has been placed on administrative duty, per standard procedure.

The suspect was then confirmed dead. Manley said they are not naming the suspect until next of kin has been notified. Plohetski reports that the suspect is from Central Texas.

Police do not have a motive yet and do not know if the suspect was planning on delivering another bomb at the time of his death.

Manley said at a press conference shortly after the suspect's death that "it's been a long almost three weeks," and this is the culmination of the hard work of multiple agencies.

Chief Manley said they "don't know where the suspect has been the past 24 hours," and that there may be other devices out there. The public must remain vigilant and call 911 if they see anything suspicious.

According to the Associated Press, an ATF agent said investigators think the suspect built all of the bombs — but they haven't ruled out that he had help.

Round Rock police said all lanes of southbound I-35 from FM 3406 and Old Settlers Road to U.S. 79 and Sam Bass Road would be closed the morning of Wednesday, March 21, while police investigate. Round Rock ISD said classes would run as scheduled but added that they would accept late arrivals due to traffic.

An investigator on the scene told ABC News, "The hunt for the bomber was a race against time as law enforcement feared additional devices would continue to be exploded."

"In the law enforcement mantra of 'stop the killing,' investigators paid less attention to why or how the suspected bomber was doing his work and instead put all of their efforts and resources into finding him and 'neutralizing the threat,'" the investigator said.

The investigation continues, though.

“Now we have to go and work backward to figure everything else out,” the investigator told ABC News.